Display system having flexible gear

ABSTRACT

A display system having a collapsible pole, an electromechanical operating system to alternately extend and retract said pole. An electrical control system selectively actuates the operating system.

United States Patent 1191 Henderson June 26,1973

1 1 DISPLAY SYSTEM HAVING FLEXIBLE GEAR [76] Inventor: Harvey Henderson, 93] l Tahiti Circle, Huntington Beach, Calif.

[22] Filed: Oct. 12, 1970 [21] Appl. No.: 80,040

[52] U.S. Cl. 340/371 R, 340/286 R [51] Int. Cl. G08b 5/00 [58] Field of Search 340/235 R, 87 R,

[56] References Cited UNITED STATES PATENTS 2,663,861 12/1953 71mm ..34o/2ss 8/1961 Kiekhaefer ..340/87'X 3,021,513 2/1962 Lankey 340/286 T 3,091,757 5/1963 Brock. 340/286 T 3,122,609 2/1964 Moore 340/286 T 3,128,448 5/1964 Shumer 340/87 3,143,722 8/1964 Murch 340/87 X 3,520,273 7/1970 Daifotes 340/87 X 3,579,814 5/1971 Forestal'. 340/87 X Primary Exqminer-'Haro1d l. Pitts Att0rney-Robert W. Fulwider [57] ABSTRACT A display system having a collapsible pole, an :electromechanical operating system to alternately extend and retract said pole. An electrical control system selectively actuates the operatingsystem.

21 Claims, 7 Drawing Figures Patented June 26, 1973 3,742,490

3 Sheets-Sheefi 1 Fig. 5.

v 69 ks? H4 63 5 68 73 93 77 i 7' I 7 H2 92 v 94 Harvey Henderson, 95 96 lN\B/$NTOR.

M 444. W) I ATTORNEY.

Patented June 26, 1973 3 Sheets-Sheet 2 Fig. 5.

Harvey Henderson,

INVENTOR. BY. I mflwfl. yu /jg ATTORNEY.

3 Sheets-Sheet 3 Patented June 26, 1973 Harvey Henderson,

INVENTOR.

7, a, ATTORNEY.

LEET

V .ls 5 mm. m 8 ow L DISPLAY SYSTEM HAVING FLEXIBLE GEAR BACKGROUND OF'TI-IE INVENTION At present there are a variety of situations wherein it is necessary and important that a visual signal be prominently displayed promptly upon the occurrence of a particular event. For example, when'engaging in the sport of water skiing, it is required that when the water skier falls down, that a danger flag be immediately raised from the towing boat to warn other boats in the area that such event has occurred. At present the .cus tomary method of complying with such requirement is to simply carry a flag pole in the boat, and when the water skier falls down, this flag pole is manually raised and, possibly, inserted into a suitable receptacle to maintain its raised position while the towing boat is retrieving the downed water skier. Such simple arranger'nent, however, presents substantial operating prob: lems, particularly where there is only a single person operating the towing boat. For example, when the water skier falls down, there is a substantial conflict between the actions involved in maneuvering the boat to return to retrieve the downed water skier, and to raise the danger flag which effectively delays one or the other. Also, it is common for the towing boat personnel to have their attention diverted during various periods of time to objects other than the water skier, so that the event of the water skier falling down is not immediately noticed. Such typicalevent can very substantially delay the retrieval of the downed water skier and create a dangerous situation by the failure to immediately raise a danger flag. Perhaps, most important of all, is the problem of the tendency of some towing boat personnel to simply ignore or forget to follow the requirement of raising the danger flag when the skier falls down. Thus, it is important that the raising of the danger flag occur automatically upon the falling down of the water skier. Finally, the elongated flag pole presently used to display the danger flag in such situations represents an item that is not only easily lost or misplaced, but also relatively clumsy and awkward to handle, particularly if it is of such a length to present a prominent display. I

In response to such problems and shortcomings of the present display warning systems, the object of the present invention is a compact, automatic display system adapted to promptly extend and subsequently retract a prominent signal in response to a predetermined actuating event, such as the falling down of a water skier.

Another object of the invention is a collapsible pole means adapted to mechanically extend and retract and to display the warning flag.

Still another object of the present invention is an electromechanical operating system for alternately extending and retracting the aforementioned pole means.

Still another object of the present invention is a simple electrical control system to selectively actuate the electromechanical operating system.

Still another object of the present invention is a flexible gear having substantial compressive strength and adapted to be linearly extended and to be compactly coiled during retraction.

Other objects and advantages of the present invention will be readily apparent from the following description and drawings which are illustrative of a preferred exemplary embodiment of the present invention.

SUMMARY OF THE INVENTION The present invention involves a collapsible pole means adapted to be mechanically extended and retracted and to display a flag thereon. Such extension drawings of-a preferred specific embodiment of the present invention. Such drawings, like the preceding summary, should not be construed as limiting the present invention which is properly set forth in the appended claims.

' DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view'of the display system of the present invention as installed in a towing boat.

FIG. 2 is an enlarged view of a portion of FIG. 1, illustrating the collapsible pole means and 'a portion of the operating electromechanical system of the present invention.

FIG. 3 is a side view of a portion of FIG. 2, taken along the lines 3 '3 of FIG.'2.

FIG. 4 is an enlarged view of another portion of FIG. 1, showing a portion of the electrical control system of the present invention.

FIG. 5 is a schematic electrical circuit diagram of the electrical control system and a portion of the electromechanical operating system of one embodiment'of the present invention. I

FIG. 6 is a side view of a portion of the flexible gear 40 taken along lines 6 6.

FIG. 7 is a schematic electrical circuit diagram of the electrical control system and a portion of the electromechanical operating system of another embodiment of the present invention.

I DESCRIPTION OF THE PREFERRED EMBODIMENT OF THE PRESENT INVENTION As illustrated in FIGS. 1 7, the display system 10 is a compact automatic display system, adapted to promptly extend and subsequently retract a prominent signal flag on a towing boat 11, in response to the predetermined actuating event of a water skier falling down and then subsequently rising to towed position. The display system 10 comprises a collapsible pole means 20, adapted to be mechanically extended and retracted and to display a flag thereon, an electromechanical operating system 60, adapted to alternately tend and retract the tube set 21. The flag 26 is securely attached along one edge to an elastic rope 27, which has one end 28 attached to the outer end 29 of the innermost tube 25 by a bracket 30, and the other end 31 attached to the outer end 32 of the adjoining tube 24 chor stud 44, and the metal base strip 43 extends beyond the end of the front strip 41 in a continuation of such spiral winding to form a coiled spring 45 whose end 46 is attached to the anchor stud 44. Such spiral winding of the flexible gear 40 in connection with the coiled spring 45 acts as a guide means to insure that the flexible gear 40 upon retraction will always form the same spirally wound configuration, and facilitates the retraction of the pole means 20. The outer end 48 of the flexible gear 40 is attached to the inner end 34 of the innermost tube 25. The flexible gear 40 has a first notch 47 adjacent its outer end 48 adapted to receive the actuating prong 81, of the retraction switch 78, when the flexible gear 40 is in its retracted position and a second notch 49 adjacent its inner end 46 adapted to receive the prong 79, of the extension switch 74, when the flexible gear is in its extended position. The drive means 50 of the collapsible pole means 20 comprises an electric motor 51 operating a gear set 52 of gears 53a, 53b, 54a, 54b, 55a, 55b, and 56, with the terminal gear 56 engaging the gear teeth 42, of the flexible gear 40 through an opening 38 in the tube 22. The gear set 52 is adapted to adjust the rotational speed of the electric motor 51 to the desired rate of travel for the flexible gear 40 during the extension and retraction and to increase the driving force applied to the flexible gear 40. Opposite the terminal gear 56 is a gear tension assembly 57, having a roller 58, extending through an opening 37 in the tube 22 and mounted on a base 59 adapted to maintain the engagement of terminal gear 56 with the flexible gear 40.

The electromechanical operating system 60 of the display system comprises a power supply 61 and a double pole, double throw relay 62, connected to the power supply 61 by leads 63 and 64 which are joined to the center contacts 65 and 66, respectively, of the relay 62. The relay 62 and the pole means are joined by a relay circuit 67, adapted to extend the pole means 20 when the relay 62 is in a normally open first position and retract the pole means 20 when the relay 62 is in a normally closed second position. The relay circuit 67 includes the leads 71 and 72 connected to the first set of contacts 69 and 70, respectively, of the relay 62 with which the relay armature 68 makes circuit closure when the relay is in its first position. The lead 71 is joined directly to the motor 51 while the lead 72 is joined to the common lead 73 through the extension switch 74. The common lead 73, in turn, is connected directly to the electric motor 51. The electrical connection between the power source 61, and the electric motor 51 through the relay 62 is adapted to cause the electric motor 51 to rotate in a clockwise direction (as displayed in FIG. 2), when the armature 68 of the relay 62 is in its first position. The relay 62 has the second set of contacts 75 and 76 with the contact 76 connected directly to the electric motor by the lead 71, and the contact 75 connected by a lead 77 through the common lead 73 through the retraction switch 78. The

power supply 61 and electric motor 51 are connected through the relay 62 so that when the armature 68 of the relay 62 is in its second position, theelectric motor 51 rotates in a counter-clockwise direction.

The extension switch 74 of the electromechanical operating system 60 is adapted to stop the extension of the pole means 20, when it reaches its final extended position. The extension switch 74 has an actuating prong 79, extending through an opening 35 in the tube 22 and an outer end 80 which contacts the underside of the flexible gear 40. When the notch 49 in the flexible gear 40 adjoins the opening 35 in the tube 22, the prong 79 extends to open the normally closed extension switch 74. The retraction switch 78 in the relay circuit 62 is adapted to stop the retraction of the pole means 20 when it reaches its final retracted position. The retraction switch 78 has an actuating prong 81, which extends through an opening 36 in the tube 22 and whose end 82 is in contact with the underside of the flexible gear 40. When the notch 47 in the flexible gear 40 is adjacent the opening 36, the prong 81 is extended to open the normally closed retraction switch 74. Thus, the extension switch 74 and retraction switch 78 are each actuated by the notches 49 and 47 respectively in the flexible gear 40 of the pole means 20, when it reaches its final extended position and final retracted position, respectively.

The electrical control system of the display system 10 comprises a connection circuit 91, having a first lead 92 joining the first end 93 of the coil 94 of the relay 62, directly to the power supply 61, and a second lead 95, joining the second end 96 of the coil 94 to the power supply 61 through an actuating switch 97 which is adapted to be closed by the immersion of said switch in water, and opened by its removal from water and which is located in the tow rope 106 adjacent the water skier. The actuating switch 97 includes an inner conductor rod 98, located within and spaced from an outer conductor cylinder 99, with both the inner conductor cylinder rod 98 and the outer conductor cylinder 99 mounted on an insulating block 100 and having apertures 101 to permit easy passage of water. The electrical control system 90 includes a strong fabric sleeve 105 enclosing the major portion of the leads 95 and 102 which are spirally wound on a central cable 107 substantially along the length of the tow rope 106. As shown in FIG. 5, the electrical control system 90 includes a skier communication system 110 having a lead 111 connected directly to the power supply 61 and second lead 112 connected to the power supply 61 through a signal switch 113 located in the tow rope 106 adjacent the water skier, and a buzzer 114 located in the tow boat 11. Such arrangement of the buzzer 114 and signal switch 113 permits the water skier to conveniently signal the tow boat operator.

As shown in FIG. 7, an alternate embodiment of the electrical control system 90 includes not only the corresponding circuit portions set forth in FIG. 5 such as connection circuit 91 and a skier communication system 1 10 but also a skier position signal system 120. The skier communication system 110 is changed to reflect the fact that its signal switch 113 is adjacent the skier and that length of the leads 121 and 111 to the signal switch 113 would substantially reduce the voltage available to the buzzer 114. Consequently the lead 112 connects the switch 113 through a coil 115 of the relay 116 to the power supply 61. Also the armature 117 of the relay 116 in the short lead 118 connects the buzzer 114 to the power supply 61 when the switch 113 is closed and the relay 116 is thereby closed.

The skier position signal system 120 includes leads 121 and 122 from the power supply 61 to which the connection circuit 91 and the skier communication system 110 are connected and across which is connected coil 123 of the single pole double throw relay 124. The armature 125 of relay 124 is connected by lead 126 to lead 121 before the switch 97. The relay 124 has a normally closed first contact 127 joined by lead 129 to coil 130 of relay 131 and to a parallel capacitor 132 and resistance 133 and a normally open second contact 128 joined by lead 134 to the armature 135 of the single pole double throw relay 131. The parallel capacitor 132 and resistance 133 are connected to the power supply 61 by lead 136 and the coil 130 is connected to the power supply 61 by lead 137. The relay 131 has a normally closed first contact 138 joined by lead 139 through a light 140 to the power supply 61 and a normally open second contact 141 joined by lead 142 through the buzzer 114 to the power supply 61.

The materials used for constructing the present invention will be obvious to one skilled in the art in view of the foregoing description. For example, the outer conducting cylinder 99 and inner conducting rod 98 may be constructed of copper, aluminum, or other suitable conducting metal. Similarly, the elastic rope 27 on which the flag 26 is mounted, may be formed of natural or synthetic rubber, or other suitable elastic material. Also the tow rope 106 and sleeve 105 may be formed of high strength fibers such as nylon.

The operation of the display System is adapted to promptly extend and subsequently retract the flag in response to the position of the water skier with respect to the water. In operation, while the water skier is being towed in an upright position, the collapsible pole means 20 is located in its retracted position with the relay 62 having its armature 68 in contact with its normally closed first contacts, 75 and 76, and the retraction switch 78 is in an open position, because of the extension of the prong 81 into the notch 47 of the flexible gear 40. Similarly, the extension switch 74 is in a closed position because the notch 49 is not adjacent the opening 35 of the tube 22. Also, despite the very large vary ing force on the tow rope 106 which causes substantial longitudinal flexing, the leads 95 and 102 are subjected to minimal stress because of the stretching of their spiral loops and because of the strength of sleeve 105 and cable 107 which takes up most of the stress caused by the flexing of the tow rope 106. If the water skier then falls down, the actuating switch 97 is filled with water which forms a connection between the inner conductor rod 98 and outer conductor cylinder 99 and closes the actuating switch 97. The closing of the actuating switch 97, in turn, actuates the relay coil 94 and causes the armature 68 to switch into contact with its normally opened contacts 69 and 70. Such change in relay position energizes the electric motor 51 to rotate the terminal gear 56 in counter-clockwise rotation, and extend the flexible gear 40 which extension closes retraction switch 78. The extension of the flexible gear 40 causes the set of tubes 21 to extend, except for the tube 25, which is held in its closed position by the elastic rope 27 until the remaining tubes 23 and 24 attain their extended position. When the remaining tubes 23 and 24 attain their fully extended position, the flexible gear 40 then continues to extend with sufficient force to overcome the restraining force of the elastic rope 27 and causes the tube 25 to attain its fully extended position. At such point, the notch 49 reaches a position adjacent the opening 35 causing the prong 79 to extend and open the extension switch 74 which, in turn, stops the motor 51.

When the water skier again attains an upright position, the water is removed from between the inner conductor rod 98 and outer conductor cylinder 99, which opens the actuating switch 97 and de-energizes the relay coil 94. When the coil 94 is de-energized, the armature 68 of the relay 62 returns to its normally closed position in contact with contacts 75 and 76 and energizes the motor 51 through the closed retraction switch 78 to rotate the terminal gear 56 in a clockwise direction. Such rotation causes the flexible gear 42 to retract which, in turn, causes the extension switch 74 to close and the tube 25 to initially retract because of the elastic force of the elastic rope 27. After the tube 25 has reached its fully retracted position, the flexible gear 40 continues its retraction motion, causing the remaining tubes 23 and 24 to retract until they also reach their fully retracted position. After all of the tubes 23, 24 and 25 reach their fully retracted position, the notch 47 again becomes positioned adjacent to retraction switch 78, so that the prong 81 is received in the notch 47 which opens the retraction switch 78 stopping the motor 51. Thus, the system can extend and retract the flag an indefinite number of times in response to' whether the water skier is in an upright position or has fallen down.

In addition to the operation of the collapsible pole means 20, the skier position signal system operates in response to the position of the water skier with respect to the water. When the skier is being towed in an upright position, the actuating switch 97 is open, and the armature of relay 124 contacts contact 127 which maintains capacitor 132 in a discharged state. Also armature 135 of relay 131 contacts contact 138 however light 140 is not actuated because there is no power being supplied to armature 135. If the water skier falls down, the actuating switch 97 is closed so the actuation of coil 123 causes armature 125 to make contact with contact 128 supplying power to armature 135. Simultaneously capacitor 132 is charged through coil 130 with the rate of charge controlled by resistance 133. During the period of such charging, coil 130 causes armature to make contact with contact 141 so that buzzer 114 is actuated. When capacitor 132 is charged, armature 135 again contacts contact 138 to turn light 140 on. When actuating switch 97 is again opened by the skier returning to an upright position, the skier position signal system 120 returns to its initial state with the capacitor 132 being discharged.

It will be appreciated that many other specific embodiments of the present invention will be obvious to one skilled in the arts in view of the disclosure of the preferred embodiment of the present invention. For example, other electromechanical operating systems may be adapted to alternately extend and retract the collapsible pole means and similarly other electrical control circuits may be adapted to selectively actuate the electromechanical operating system. In addition the electrical control circuit may include additional features such as the skier position signal system may include an additional resistance to show the discharge of the capacitor or two buzzers, one for the up position and one for the down position. Similarly, other gear systems such as a screw gear may be utilized to drive the flexible gear. However, most important, the flexible gear may consist of a single strong flexible material adapted to sustain substantial tensive and compressive force, to be linearly extended and retracted, and to permit compact coiling. Such material may include plastics such as Nylon or Delron.

There are many features of the present invention which clearly show the significance which the present invention achieves over the prior art. Consequently, only a few of the more outstanding features will be pointed out to illustrate the unexpected and unusual results obtained by the present invention. One feature of the present invention is that the display system utilizes a collapsible pole means which is mechanically extended and retracted by a flexible gear, which provides a simple compact drive means and permits a simple control means for its operation. Another feature of the present invention is the utilization of an elastic rope to mount the display flag on the telescoping tube which permits the flag to be extended only during the most extended portion of the retraction and extension cycle. Thus, the wind resistance and resulting bending force on the telescoping tubes is substantially eliminated and permits a smooth operation during both extension and retraction of the collapsible polemeans. Still another feature of the present invention is the actuating switch whose closing is achieved by immersion of this switch in water. Such action insures that the operation of the display system occurs only when the water skier is down. Still another feature of the present invention is the use of a tow rope having a central cable with lead wires spirally wound along its length and a strong fabric sleeve enclosing them both so that when towing the water skier the stretch of the tow rope is minimized by the cable and sleeve and the stress on the lead wires is substantially eliminated by the expansion of the spiral configuration. Another feature of the present invention is the positioning of a signal switch in the tow rope adjacent the water skier which operates a buzzer in the tow boat so that the water skier can simply communicate with the tow boat operator by manually operating the signal switch. Still another feature of the present invention is the skier position signal system which provides an immediate brief audible signal followed by a continuing visual signal when the skier falls down. Still another feature of the present invention is a flexible gear capable of being repeatedly coiled into a small space and then extended and of supporting substantial compressive and tensive forces.

It will be understood that the foregoing description and drawings are only illustrative of the present invention and it is not intended that the invention be limited thereto. All substitutions, alterations and modifications of the present invention which come within the scope of the following claims or to which the present invention is readily susceptible without departing from the spirit and scope of this disclosure are considered part of the present invention.

I claim:

1. A compact automatic display system adapted to promptly extend and subsequently retract a prominent signal in response to a predetermined actuating event comprising:

a. a collapsible pole means adapted to be mechanically extended and retracted and to display a flag thereon, comprising: I. a set of telescoping tubes with the innermost tube and adjoining tube having a flag mounted therebetween on an elastic rope attached to the outer end of said innermost tube and the outer end of said adjoining tube with said elastic rope requiring a stretch force for substantial extension in excess of the extension force for extending said tube set;

II. a flexible gear adapted to extend and retract said tube set and to be compactly coiled during the retraction of said tube set; and,

III. drive means for moving said flexible gear to extend and retract the tube set;

b. an electromechanical operating system adapted to alternately extend and retract said pole means comprising:

i. a power supply;

ll. a double pole, double throw relay connected to said power supply;

III. a relay circuit joining said relay and said pole means adapted to extend said pole means when said relay is in its first position and retract'said pole means when said relay is in its second position;

IV. an extension switch in said relay circuit adapted to stop the extension of said pole means in its final extended position; and,

V. a retraction switch in said relay circuit adapted to stop the retraction of said pole means in its final retracted position, said extension switch and retraction switch each being actuated by said pole means in its extended position and retracted position, respectively.

c. an electrical control system adapted to selectively actuate the electromechanical operating system comprising a connection circuit joining said power supply and the coil of said relay and an actuating switch in said connection circuit adapted to be operated by a predetermined actuating event, said ac tuating switch comprising a first and second contact adapted to be electrically connected by an interconnecting body of water and a major portion of said connection circuit being enclosed in a strong fabric sleeve with said connection circuit portion spirally wound around a central cable which sleeve and cable extend substantially along the entire length of the tow rope. i

2. A compact automatic display system adapted to promptly extend andsubsequently retract a prominent signal in response to a predetermined event comprising:

a. collapsible pole means comprising a set of telescoping tubes adapted to be mechanically extended and retracted and to display a signal thereon;

b. an electromechanical operating system including a flexible gear adapted to alternately extend and retract said tube set and to be compactly coiled during retraction of said tube set;

c. drive means for moving said flexible gear to extend and retract said tube set; and

d. an electrical control system adapted to selectively actuate said electromechanical operating system.

3. A display system as stated in claim 2 wherein said collapsible pole means includes a flag mounted beend of the innermost tube and the outer end of the adjoining tube, said elastic rope requiring a stretch force for substantial extension in excess of the extension force for extending said tube set.

5. A display system as stated in claim 2, wherein said drive means comprises an electric motor operating a gear set with the terminal gear engaging said flexible gear.

6. A display system as stated in claim 2, wherein said electromechanical operating system includes:

a. a power supply;

b. a relay connected to said power supply;

c. a relay circuit joining said relay and said pole means, adapted to extend said pole means when said relay is in a first position, and retract said pole means when said relay is in a second position;

d. an extension switch in said relay circuit adapted to stop the extension of said pole means in its final extended position; and,

e. a retraction switch in said relay circuit adapted to stop the retraction of said pole means in its final re-, tracted position.

7. A display system as stated in claim 6, wherein said electrical control system comprises:

a. a connection circuit joining said power supply and the coil of said relay; and I b. an actuating switch in said connection circuit adapted to be operated by a predetermined actuating event.

8. A display system as stated in claim 2'wherein said electromechanical operating system includes a power supply and a relay and said electrical control system includes:

a. a connection circuit joining said power supply and the coil of saidrelay; and

b. an actuating switch in said connection circuit adapted to be operated by a predetermined actuating event.

9. A display system as stated in claim 8, wherein a major portion of said connection circuit is enclosed in a strong fabric sleeve and said connection circuit portion is spirally wound around a central cable which sleeve and cable extend substantially along the entire length of the tow rope.

10. A display system as stated in claim 8, wherein said actuating switch comprises a first and a second contact adapted to be connected electrically by an interconnecting body of water.

tween the innermost of said telescoping tubes and the I 11. A display system as stated in claim 10, whereinsaid electrical control system includes a skier communication system and a skier position signal system.

12. A display system as defined in claim 2 wherein the outer end of said flexible gear is attached to the inner end of the innermost of said telescoping tubes.

13. A display device as defined in claim 2 wherein said flexible gear comprises an elongated front strip of semi-rigid material having a series of gear teeth formed therein.

14. A display device as defined in claim 13 which includes aflexible metal strip integrally attached to the underside of said semi rigid strip.

15. A collapsible telescopic means adapted to mechanically extend and retract a warning flag or other object which comprises:

a. a housing;

b. a set of telescoping tubes with the outermost of said tubes mounted in said housing and the innermost of said tubes connected to the flag or other object to be extended and retracted;

c. a flexible gear operatively associated with said tube set to extend and retract the same and adapted to be compactly coiled within said housing during retraction of said tube set; a

(1. drive means including a gear for driving said flexible gear to extend and retract said tube set; and

e. electrical power means adapted to selectively operate said drive means to selectively extend and retract said tube set.

16. Collapsible telescopic means as defined in claim 15 which includes means for actuating said power means in response to a predetermined actuating event.

17. Collapsible telescopic means as defined in claim 15 wherein said flexible gear comprises an elongated strip of semi-rigid material having a series of gear teeth formed in one face thereof.

18. Collapsible telescopic means as defined in claim 15 including an anchor stud and said flexible gear has an extended portion without teeth therein which is attached to and spirally wound around said stud to facilitate retraction of said gear and said tube set.

19. Collapsible telescopic means as defined in claim 17 in which the power means includes limit switch means operatively associated with said gear strip for controlling the movement of said tube set.

20. Collapsible telescopic means as defined in claim 19 wherein said limit switch means comprises a pair of pin operated switches and said gear strip carries a pair of apertures for reception of said pins to operate said switches. 

1. A compact automatic display system adapted to promptly extend and subsequently retract a prominent signal in response to a predetermined actuating event comprising: a. a collapsible pole means adapted to be mechanically extended and retracted and to display a flag thereon, comprising: I. a set of telescoping tubes with the innermost tube and adjoining tube having a flag mounted therebetween on an elastic rope attached to the outer end of said innermost tube and the outer end of said adjoining tube with said elastic rope requiring a stretch force for substantial extension in excess of the extension force for extending said tube set; II. a flexible gear adapted to extend and retract said tube set and to be compactly coiled during the retraction of said tube set; and, III. drive means for moving said flexible gear to extend and retract the tube set; b. an electromechanical operating system adapted to alternately extend and retract said pole means comprising: I. a power supply; II. a double pole, double throw relay connected to said power supply; III. a relay circuit joining said relay and said pole means adapted to extend said pole means when said relay is in its first position and retract said pole means when said relay is in its second position; IV. an extension switch in said relay circuit adapted to stop the extension of said pole means in its final extended position; and, V. a retraction switch in said relay circuit adapted to stop the retraction of said pole means in its final retracted position, said extension switch and retraction switch each being actuated by said pole means in its extended position and retracted position, respectively. c. an electrical control system adapted to selectively actuate the electromechanical operating system comprising a connection circuit joining said power supply and the coil of said relay and an actuating switch in said connection circuit adapted to be operated by a predetermined actuating event, said actuating switch comprising a first and second contact adapted to be electrically connected by an interconnecting body of water and a major portion of said connection circuit being enclosed in a strong fabric sleeve with said connection circuit portion spirally wound around a central cable which sleeve and cable extend substantially along the entire length of the tow rope.
 2. A compact automatic display system adapted to promptly extend and subsequently retract a prominent signal in response to a predetermined event comprising: a. collapsible pole means comprising a set of telescoping tubes adapted to be mechanically extended and retracted and to display a signal thereon; b. an electromechanical operating system including a flexible gear adapted to alternately extend and retract said tube set and to be compactly coiled during retraction of said tube set; c. drive means for moving said flexible gear to extend and retract said tube sEt; and d. an electrical control system adapted to selectively actuate said electromechanical operating system.
 3. A display system as stated in claim 2 wherein said collapsible pole means includes a flag mounted between the innermost of said telescoping tubes and the tube adjacent thereto.
 4. A display system as stated in claim 3, wherein said flag is mounted on an elastic rope attached to the outer end of the innermost tube and the outer end of the adjoining tube, said elastic rope requiring a stretch force for substantial extension in excess of the extension force for extending said tube set.
 5. A display system as stated in claim 2, wherein said drive means comprises an electric motor operating a gear set with the terminal gear engaging said flexible gear.
 6. A display system as stated in claim 2, wherein said electromechanical operating system includes: a. a power supply; b. a relay connected to said power supply; c. a relay circuit joining said relay and said pole means, adapted to extend said pole means when said relay is in a first position, and retract said pole means when said relay is in a second position; d. an extension switch in said relay circuit adapted to stop the extension of said pole means in its final extended position; and, e. a retraction switch in said relay circuit adapted to stop the retraction of said pole means in its final retracted position.
 7. A display system as stated in claim 6, wherein said electrical control system comprises: a. a connection circuit joining said power supply and the coil of said relay; and b. an actuating switch in said connection circuit adapted to be operated by a predetermined actuating event.
 8. A display system as stated in claim 2 wherein said electromechanical operating system includes a power supply and a relay and said electrical control system includes: a. a connection circuit joining said power supply and the coil of said relay; and b. an actuating switch in said connection circuit adapted to be operated by a predetermined actuating event.
 9. A display system as stated in claim 8, wherein a major portion of said connection circuit is enclosed in a strong fabric sleeve and said connection circuit portion is spirally wound around a central cable which sleeve and cable extend substantially along the entire length of the tow rope.
 10. A display system as stated in claim 8, wherein said actuating switch comprises a first and a second contact adapted to be connected electrically by an interconnecting body of water.
 11. A display system as stated in claim 10, wherein said electrical control system includes a skier communication system and a skier position signal system.
 12. A display system as defined in claim 2 wherein the outer end of said flexible gear is attached to the inner end of the innermost of said telescoping tubes.
 13. A display device as defined in claim 2 wherein said flexible gear comprises an elongated front strip of semi-rigid material having a series of gear teeth formed therein.
 14. A display device as defined in claim 13 which includes a flexible metal strip integrally attached to the underside of said semi rigid strip.
 15. A collapsible telescopic means adapted to mechanically extend and retract a warning flag or other object which comprises: a. a housing; b. a set of telescoping tubes with the outermost of said tubes mounted in said housing and the innermost of said tubes connected to the flag or other object to be extended and retracted; c. a flexible gear operatively associated with said tube set to extend and retract the same and adapted to be compactly coiled within said housing during retraction of said tube set; d. drive means including a gear for driving said flexible gear to extend and retract said tube set; and e. electrical power means adapted to selectively operate said drive means to selectively extend and retract said tube set.
 16. Collapsible telescopic means as defineD in claim 15 which includes means for actuating said power means in response to a predetermined actuating event.
 17. Collapsible telescopic means as defined in claim 15 wherein said flexible gear comprises an elongated strip of semi-rigid material having a series of gear teeth formed in one face thereof.
 18. Collapsible telescopic means as defined in claim 15 including an anchor stud and said flexible gear has an extended portion without teeth therein which is attached to and spirally wound around said stud to facilitate retraction of said gear and said tube set.
 19. Collapsible telescopic means as defined in claim 17 in which the power means includes limit switch means operatively associated with said gear strip for controlling the movement of said tube set.
 20. Collapsible telescopic means as defined in claim 19 wherein said limit switch means comprises a pair of pin operated switches and said gear strip carries a pair of apertures for reception of said pins to operate said switches.
 21. Collapsible telescopic means as defined in claim 17 wherein said flexible gear includes a flexible metal strip integrally attached to the underside of said semi-rigid strip. 